Reporting of quality attributes in scientific publications presenting biosimilarity assessments of (intended) biosimilars: a systematic literature review

An Overview of Biosimilars-Development, Quality, Regulatory Issues, and Management in Healthcare

Biological therapies have transformed high-burden treatments. As the patent and exclusivity period for biological medicines draws to a close, there is a possibility for the development and authorization of biosimilars. These products boast comparable levels of safety, quality, and effectiveness to their precursor reference products. Biosimilars, although similar to reference products, are not identical copies and should not be considered generic substitutes for the original. Their development and evaluation involve a rigorous step-by-step process that includes analytical, functional, and nonclinical evaluations and clinical trials. Clinical studies conducted for biosimilars aim to establish similar efficacy, safety, and immunogenicity, rather than demonstrating a clinical benefit, as with the reference product. However, although the current knowledge regarding biosimilars has significantly increased, several controversies and misconceptions still exist regarding their immunogenicity, extrapolation, interchangeability, substitution, and nomenclature. The development of biosimilars stimulates market competition, contributes toward healthcare sustainability, and allows for greater patient access. However, maximizing the benefits of biosimilars requires cooperation between regulators and developers to ensure that patients can benefit quickly from access to these new therapeutic alternatives while maintaining high standards of quality, safety, and efficacy. Recognizing the inherent complexities of comprehending biosimilars fully, it is essential to focus on realistic approaches, such as fostering open communication between healthcare providers and patients, encouraging informed decision-making, and minimizing risks. This review addresses the regulatory and manufacturing requirements for biosimilars and provides clinicians with relevant insights for informed prescribing.

Characterization of Higher Order Structural Changes of a Thermally Stressed Monoclonal Antibody via Mass Spectrometry Footprinting and Other Biophysical Approaches

Characterizing changes in the higher order structure (HOS) of monoclonal antibodies upon stressed conditions is critical to gaining a better understanding of the product and process. One single biophysical approach may not be best suited to assess HOS comprehensively; thus, the synergy from multiple, complementary approaches improves characterization accuracy and resolution. In this study, we employed two mass spectrometry (MS )-based footprinting techniques, namely, fast photochemical oxidation of proteins (FPOP)-MS and hydrogen-deuterium exchange (HDX)-MS, supported by dynamic light scattering (DLS), differential scanning calorimetry (DSC), circular dichroism (CD), and nuclear magnetic resonance (NMR) to study changes to the HOS of a mAb upon thermal stress. The biophysical techniques report a nuanced characterization of the HOS in which CD detects no changes to the secondary or tertiary structure, yet DLS measurements show an increase in the hydrodynamic radius. DSC indicates that the stability decreases, and chemical or conformational changes accumulate with incubation time according to NMR. Furthermore, whereas HDX-MS does not indicate HOS changes, FPOP-MS footprinting reveals conformational changes at residue resolution for some amino acids. The local phenomena observed with FPOP-MS indicate that several residues show various patterns of degradation during thermal stress: no change, an increase in solvent exposure, and a biphasic response to solvent exposure. All evidences show that FPOP-MS efficiently resolves subtle structural changes and novel degradation pathways upon thermal stress treatment at residue-level resolution.

Multi-attribute method (MAM) to assess analytical comparability of adalimumab biosimilars

Adalimumab drug product (Humira ®), the first fully human monoclonal antibody (mAb) approved by FDA in 2002, led the top ten list of best-selling mAbs in 2018 and has been the most profitable drug in the world. With the expiration of patent protection in Europe in 2018 and in United States by 2023, the landscape is changing as up to 10 adalimumab biosimilars are expected to enter the market in the US. Biosimilars offer the potential to lower costs on health care systems and increase patient accessibility. The analytical similarity of seven different adalimumab biosimilars was accomplished in the present study using the multi-attribute method (MAM), a LC-MS based peptide mapping technique that allows for primary sequence assessment and evaluation of multiple quality attributes including deamidation, oxidation, succinimide formation, N- and C- terminal composition and detailed N-glycosylation analysis. In the first step, characterization of the most relevant post-translational modifications of a reference product was attained during the discovery phase of MAM. During the second step, as part of the MAM targeted monitoring phase, adalimumab batch-to batch variability was evaluated to define statistical intervals for the establishment of similarity ranges. The third step describes biosimilarity evaluation of predefined quality attributes and new peak detection for the assessment of any new or modified peak compared to the reference product. This study highlights a new perspective of the MAM approach and its underlying power for biotherapeutic comparability exercises in addition to analytical characterization. MAM offers a streamlined comparability assessment workflow based on high-confidence quality attribute analysis using high-resolution accurate mass mass spectrometry (HRAM MS) and the capability to detect any new or modified peak compared to the reference product.

Analytical sameness methodology for the evaluation of structural, physicochemical, and biological characteristics of Armlupeg: A pegfilgrastim biosimilar case study

Pegfilgrastim is administered as an adjunct to chemotherapy to reduce the incidence of febrile neutropenia and associated infectious complications. Lupin's Pegfilgrastim is a proposed biosimilar to the U.S.-referenced Neulasta®. Demonstration of biosimilarity requires extensive physicochemical and functional characterization of the biosimilar, and demonstration of analytical similarity to the reference product, in addition to clinical studies. This work is a case study for demonstrating the analytical similarity of Armlupeg (Lupin's Pegfilgrastim) to Neulasta® with respect to structural and physicochemical attributes using several robust, orthogonal, and state-of-the-art techniques including high-end liquid chromatography, mass spectrometry, and spectroscopy techniques; circular dichroism; differential scanning calorimetry; nuclear magnetic resonance; analytical ultracentrifugation; and micro-flow imaging. Functional similarity was demonstrated using an in vitro cell proliferation assay to measure relative potency and surface plasmon resonance to measure receptor binding kinetics. Furthermore, comparative forced-degradation studies were performed to study the degradation of the products under stress conditions. The product attributes were ranked based on a critical quality attributes risk score according to their potential clinical impact. Based on criticality, all analyses were statistically evaluated to conclude analytical similarity. Lupin's Pegfilgrastim was comparable to Neulasta® as demonstrated via structural, functional, and purity analyses. Lupin's Pegfilgrastim complied with the quality and statistical ranges established using Neulasta®. Both products follow the same degradation pathways under stress conditions as observed in the forced-degradation studies. No new impurity or degradation product was observed in Lupin's Pegfilgrastim. These data conclusively demonstrate the analytical similarity of Lupin's Pegfilgrastim and Neulasta®.

Demonstrating analytical similarity of a biosimilar HLX04 to bevacizumab with a panel of state-of-the-art methods and tiering of quality attributes

Therapeutical monoclonal antibodies are structurally and functionally complex, whereas the innovator's manufacturing processes are proprietary. With respect to the similarity assessment, a proposed biosimilar product needs to demonstrate a side-by-side comparison between the reference product (RP) and candidate product in terms of physicochemical properties and biological activities, as well as nonclinical and clinical outcomes. Here, a comprehensive analytical similarity assessment was performed for in-depth comparison of HLX04, China-sourced Avastin^® (CN-Avastin^®), and Europe-sourced Avastin^® (EU-Avastin^®) following a tier-based quality attribute (QA) evaluation. A series of orthogonal and state-of-the-art analytical techniques were developed for the assessment. Ten lots of HLX04 were compared with 29 lots bevacizumab RP. Referred to the characterization results, HLX04 is highly similar to the RPs with respect to physicochemical properties and biological functions. In addition, HLX04 was found with similar stability and degradation behaviors upon multiple stressed conditions to bevacizumab. Minor differences were observed in glycosylation, aggregates, FcγRIIIa(F), and FcγRIIIa(V) binding activities; nevertheless, they were evaluated and demonstrated not to impact clinical outcomes. According to the reported clinical results, the totality of evidence, including the pharmacokinetic, efficacy, safety, and immunogenicity, further shows that HLX04 is similar to CN-/EU-Avastin^®.

Analytical Similarity Assessment of Biosimilars: Global Regulatory Landscape, Recent Studies and Major Advancements in Orthogonal Platforms

Biopharmaceuticals are one of the fastest-growing sectors in the biotechnology industry. Within the umbrella of biopharmaceuticals, the biosimilar segment is expanding with currently over 200 approved biosimilars, globally. The key step towards achieving a successful biosimilar approval is to establish analytical and clinical biosimilarity with the innovator. The objective of an analytical biosimilarity study is to demonstrate a highly similar profile with respect to variations in critical quality attributes (CQAs) of the biosimilar product, and these variations must lie within the range set by the innovator. This comprises a detailed comparative structural and functional characterization using appropriate, validated analytical methods to fingerprint the molecule and helps reduce the economic burden towards regulatory requirement of extensive preclinical/clinical similarity data, thus making biotechnological drugs more affordable. In the last decade, biosimilar manufacturing and associated regulations have become more established, leading to numerous approvals. Biosimilarity assessment exercises conducted towards approval are also published more frequently in the public domain. Consequently, some technical advancements in analytical sciences have also percolated to applications in analytical biosimilarity assessment. Keeping this in mind, this review aims at providing a holistic view of progresses in biosimilar analysis and approval. In this review, we have summarized the major developments in the global regulatory landscape with respect to biosimilar approvals and also catalogued biosimilarity assessment studies for recombinant DNA products available in the public domain. We have also covered recent advancements in analytical methods, orthogonal techniques, and platforms for biosimilar characterization, since 2015. The review specifically aims to serve as a comprehensive catalog for published biosimilarity assessment studies with details on analytical platform used and critical quality attributes (CQAs) covered for multiple biotherapeutic products. Through this compilation, the emergent evolution of techniques with respect to each CQA has also been charted and discussed. Lastly, the information resource of published biosimilarity assessment studies, created during literature search is anticipated to serve as a helpful reference for biopharmaceutical scientists and biosimilar developers.

The regulatory landscape of biosimilars: Algeria's efforts and progress made from 2006 to 2021

Biologics are tremendously efficacious biological molecules that have enabled the treatment of many life-threatening diseases, which have previously been hard to treat. Biosimilars, also known as "follow-on biologics", are highly similar versions of another already approved biologic, called the Reference Product. The European Union has been a pioneer in the regulation of biosimilars. WHO guideline on evaluation of biosimilars published in 2009 was an important landmark in biosimilar regulations worldwide, and several countries have adopted its principles in the development of their own regulatory pathway for the approval of biosimilars. Most countries in the Middle East North Africa (MENA) region still lack official and scientific guidelines for biosimilar approval pathways. This article explores the regulatory situation of biosimilar registration pathways in Algeria and describes the progress made and the regulatory landscape changes for biosimilars in Algeria during the past ten years. Our findings indicate that the development of biosimilar regulation in Algeria went through three major phases between 2006 and 2021, during which there has been much progress in drafting guidance documents for biosimilars. Since 2016, Algeria has used the EMA, FDA and WHO guidelines as the basis for approval of several biosimilars and no national guidelines or regulations have been adopted to date. Additionally, there has been no regulation on substitution/interchangeability. The Algerian regulatory authority has gained considerable experience with approval and use of increasingly complex biosimilars over the past 5 years and has the potential to create its own biosimilar-specific regulatory pathway in the near future.

Type and Extent of Information on (Potentially Critical) Quality Attributes Described in European Public Assessment Reports for Adalimumab Biosimilars

Regulatory approval of biosimilars predominantly relies on biosimilarity assessments of quality attributes (QAs), particularly the potentially critical QAs (pCQAs) that may affect the clinical profile. However, a limited understanding exists concerning how EU regulators reflect the biosimilarity assessments of (pC)QAs in European public assessment reports (EPARs) by different stakeholders. The type and extent of information on QAs and pCQAs in EPARs were evaluated for seven adalimumab biosimilars. Seventy-seven QAs, including 31 pCQAs, were classified and assessed for type (structural and functional attributes) and extent (biosimilarity interpretation and/or test results) of information in EPARs. Reporting on the QAs (35–75%) varied between EPARs, where the most emphasis was placed on pCQAs (65–87%). Functional attributes (54% QAs and 92% pCQAs) were reported more frequently than structural attributes (8% QAs and 22% pCQAs). About 50% (4 structural and 12 functional attributes) of pCQAs were consistently reported in all EPARs. Regulators often provided biosimilarity interpretation (QAs: 83% structural and 80% functional; pCQAs: 81% structural and 78% functional) but rarely include test results (QAs: 1% structural and 9% functional and pCQAs: 3% structural and 9% functional). Minor differences in structural attributes, commonly in glycoforms and charge variants, were often observed in adalimumab biosimilars but did not affect the functions and clinical profile. Despite the variability in reporting QAs in EPARs, the minor observed differences were largely quantitative and not essentially meaningful for the overall conclusion of biosimilarity of the seven adalimumab biosimilars.

Comparison of consistency and complementarity of reporting biosimilar quality attributes between regulatory and scientific communities: An adalimumab case study

Biosimilar approval relies on the comparability of quality attributes (QAs), for which information can be derived from regulatory or scientific communities. Limited information is known about whether these sources are consistent with or complementary to each other. The consistency and complementarity of QA reporting in biosimilarity assessments for adalimumab biosimilars approved by the European Medicines Agency in European public assessment reports (EPARs) and scientific publications was assessed. A classification of 77 different QAs (53 structural and 24 functional attributes) was used to assess the types of and information on QAs reported. Six adalimumab biosimilars were analyzed, for which the number of QAs reported in EPARs and publications varied (range = 47 [61%]-60 [78%]). The proportion of QAs consistently reported in both sources varied (range = 28%-75%) among biosimilars; functional QAs (mean = 21 QAs [88%]; range = 19-23) were more consistently reported than structural QAs (mean = 33 QAs [62%]; range = 27-34). The EPARs frequently reported biosimilarity interpretation without providing test results (9-57 QAs in EPARs versus 0-8 QAs in publications), whereas publications frequently reported both test results and interpretations (13-40 QAs in publications versus 0-3 QAs in EPARs). Both sources provided information on the biosimilarity of QAs in a complementary manner and the same biosimilarity interpretation of test results for reported QAs (mean = 90%; range = 78%-100%), with a small discrepancy in biosimilarity interpretations of a few clinically relevant QAs related to post-translation modifications and biological activity. Comprehensive reporting of QAs can contribute to an improved understanding of the role of structural and functional attributes in establishing biosimilarity and the mechanism of action of biological substances in general.